The Moench and Morrow story from The Spectre 11 (Feb 88) is another Millennium tie-in, but more of an epilogue, taking place after the events of the series have concluded. I was quite excited by it, as it was also one of the early gatherings of supernatural characters, which was a rare event in the 80s.
This story largely takes place at the house that the Spectre took "possession" of a few issues back. During the course of this story, one of the members of the Cult of the Blood Red Moon officially buys the house, knowing of its connection to the Spectre. The house is revealed to have quite a few spirits residing in it already. Dr Fate shows up first, and is a bit freaked out by the ghostly glob it sees. The Spectre is amused, since this is not the same Dr Fate that it had been teammates with in the Justice Society, this is the new Dr Fate, a merger of Eric and Linda Strauss. The Phantom Stranger is the next one to join the party, followed shortly by the Gentleman Ghost, who adds his distinctive flair to the meeting.
Meanwhile Deschanta, the Cult member who bought the house, allows a demon to feast on her in a disgusting way, empowering the spirits in the house.
Jim Corrigan and Kim Liang are curious when they see Madame Xanadu leave her home, the first time they have seen her do so. They follow her, as she travels with Zatanna, June Moone, and Ben Turner, the Bronze Tiger. June is the Enchantress, and in an issue of Suicide Squad Xanadu gave Ben a ring that allows him to keep her under control when the Enchantress' power drives her mad.
Mention is made of John Constantine and Swamp Thing, who are not coming, and Baron Winters calls, but also does not attend. The house itself notices Jim and Kim spying, and grabs them, pulling them inside.
Deadman is the last to arrive, possessing Jim Corrigan's body and making him walk on his hands. By then Ben has noticed his ring missing, and the Enchantress goes nuts, thanks to the manipulations of the Cult. She levitates the house, intending to crush a group of gay rights protestors. That's a bit weird, there is no obvious reason the Enchantress should hate them.
Dr Fate keeps the house afloat while the Spectre and Madame Xanadu find the ring being shielded by the ghostly glob thing, and get it back. Only then do the characters actually get to the reason for their meeting, to determine how the events of Millennium, and the coming evolution of humans, will affect them. It's not much of a discussion, since they all decide to just keep doing what they are doing. But that's fine, the distraction provided by the Cult and the Enchantress kept the story going.
And though they did not manage to kill any of those attending the meeting, the Cult of the Blood Red Moon considers this gambit a success as well. They have a really low bar for success.